//
//  WJStatusPictureView.swift
//  新浪微博swift
//
//  Created by WJ-Jason on 2017/6/13.
//  Copyright © 2017年 WJ-Jason. All rights reserved.
//

import UIKit

class WJStatusPictureView: UIView {
    
    var viewModel : WJStatusViewModel? {
        didSet {
            calcViewSize()
            
            // 设置 urlS
            urls = viewModel?.picURLs
        }
    }
    
    private func calcViewSize() {
        // 处理宽度
        // 1> 单图，根据配图视图的大小，修改 subviews[0] 的宽高
        if viewModel?.picURLs?.count == 1 {
            let viewSize = viewModel?.pictureViewSize ?? CGSize()
            
            // a) 获取第0个图像视图
            let v = subviews[0]
            v.frame = CGRect(x: 0,
                             y: WBStatusPictureViewOutterMargin,
                             width: viewSize.width,
                             height: viewSize.height - WBStatusPictureViewOutterMargin)
        } else {
            // 2> 多图(无图)，回复 subview[0] 的宽高，保证九宫格布局的完整
            
            let v = subviews[0]
            v.frame = CGRect(x: 0,
                             y: WBStatusPictureViewOutterMargin,
                             width: WBStatusPictureItemWidth,
                             height: WBStatusPictureItemWidth)
        }
        
        // 修改高度约束
        heightCons.constant = viewModel?.pictureViewSize.height ?? 0    }
    
    /// 配图视图的数组
    var urls : [WJStatusPicture]? {
        didSet {
            // 1.隐藏所有的ImageView
            for v in subviews {
                v.isHidden = true
            }
            
            // 2. 遍历urls数组 顺序设置图像
            var index = 0
            for url in urls ?? [] {
                // 获得对应索引的 imageView
                let iv = subviews[index] as! UIImageView
                
                // 4张图像处理
                if index == 1 && urls?.count  == 4 {
                    index += 1
                }
                
                // 加载图像
                iv.cz_setImage(urlString: url.thumbnail_pic, placeholderImage: nil)
                
                // 显示图像
                iv.isHidden = false
                
                index += 1
            }
            
        }
    }

    @IBOutlet weak var heightCons : NSLayoutConstraint!
    
    override func awakeFromNib() {
        
        setupUI()
    }
}

// MARK: - 设置界面
extension WJStatusPictureView {
    
    // 1. Cell 中所有的控件都是提前准备好
    // 2. 设置的时候，根据数据决定是否显示
    // 3. 不要动态创建控件
    
    fileprivate func setupUI() {
        
        // 设置背景颜色
        backgroundColor = superview?.backgroundColor
        
        // 超出边界的内容不显示
        clipsToBounds = true
        
        // 循环创建9个ImageView
        let count = 3
        let rect = CGRect(x: 0,
                          y: WBStatusPictureViewOutterMargin,
                          width: WBStatusPictureItemWidth,
                          height: WBStatusPictureItemWidth)
        for i in 0..<count * count {
            let iv = UIImageView()
            
            // 设置contenMode
            iv.contentMode = .scaleAspectFill
            //超出边界的内容不显示
            iv.clipsToBounds = true
            
            // 行
            let row = CGFloat( i / count)
            // 列
            let col = CGFloat( i % count)
            
            let xOffset = col * (WBStatusPictureItemWidth + WBStatusPictureViewInnerMargin)
            let yOffset = row * (WBStatusPictureItemWidth + WBStatusPictureViewInnerMargin)
            
            iv.frame = rect.offsetBy(dx: xOffset, dy: yOffset)
            
            addSubview(iv)
        }
    }
}
